The controversial selectivity is one of the most significant limitations of the current gold standard FC, which could also be elevated in other organic gastrointestinal diseases.21 To assess the selectivity of faecal PAI-1, we collected samples from negative controls, IBD patients, and patients who had organic lesions detectable at colonoscopy except for IBD, and allocated them to six groups: negative, active IBD, inactive IBD, adenoma, colorectal cancer, and diverticulosis [without inflammation]. The gene discussed is SERPINE1; the disease is gastrointestinal disease.